Before they built an international underworld empire — before they weaseled their way onto millions of computers, before their online enterprise was bringing in hundreds of millions of dollars a year, before they were fugitives wanted by Interpol — Sam Jain, now 41, and Daniel Sundin, 33, were just a couple of garden-variety Internet hustlers...

Then they discovered how much PC users were afraid of infection by computer viruses.

The appeal of the bogus antivirus software—often called "scareware"—is
rooted in fear. This fraud doesn't rely on convincing the victim of
something preposterous—for example, that a Nigerian prince needs help
relocating his money. Instead, the delivery is calibrated to capitalize
on the real warnings we've all gotten.